feat: enhance system prompt with app context and dynamic model name

- Add App Context section describing the left/right panel layout
- Add App Features section with icon locations (history, theme, upload, export, clear)
- Dynamically inject model name into system prompt via {{MODEL_NAME}} placeholder
- Expand edit_diagram tool description with usage guidelines

app/api/chat/route.ts

@@ -282,13 +282,31 @@ Notes:
       },
       edit_diagram: {
         description: `Edit specific parts of the current diagram by replacing exact line matches. Use this tool to make targeted fixes without regenerating the entire XML.
-CRITICAL: Copy-paste the EXACT search pattern from the "Current diagram XML" in system context. Do NOT reorder attributes or reformat - the attribute order in draw.io XML varies and you MUST match it exactly.
-IMPORTANT: Keep edits concise:
-- COPY the exact mxCell line from the current XML (attribute order matters!)
-- Only include the lines that are changing, plus 1-2 surrounding lines for context if needed
-- Break large changes into multiple smaller edits
-- Each search must contain complete lines (never truncate mid-line)
-- First match only - be specific enough to target the right element`,
+
+WHEN TO USE:
+- Changing text labels or values
+- Modifying colors, styles, or visual properties
+- Adding or removing individual elements (1-3 elements)
+- Repositioning specific elements
+- Any small, targeted modification
+
+WHEN TO USE display_diagram INSTEAD:
+- Creating a new diagram from scratch
+- Major restructuring (reorganizing layout, changing diagram type)
+- Adding many new elements (more than 3)
+- After 3 failed edit_diagram attempts
+
+CRITICAL RULES:
+1. Copy-paste the EXACT search pattern from the "Current diagram XML" in system context
+2. Do NOT reorder attributes - attribute order in draw.io XML varies, you MUST match exactly
+3. Always include the element's id attribute for unique targeting
+4. Include complete lines (never truncate mid-line)
+5. For multiple changes, use separate edits in the array
+
+ERROR RECOVERY:
+- If pattern not found, check attribute order matches current XML exactly
+- Retry up to 3 times with adjusted patterns
+- After 3 failures, use display_diagram instead`,
         inputSchema: z.object({
           edits: z.array(z.object({
             search: z.string().describe("EXACT lines copied from current XML (preserve attribute order!)"),

app/layout.tsx

@@ -1,4 +1,4 @@
-import type { Metadata } from "next";
+import type { Metadata, Viewport } from "next";
 import { Plus_Jakarta_Sans, JetBrains_Mono } from "next/font/google";
 import { Analytics } from "@vercel/analytics/react";
 import { GoogleAnalytics } from "@next/third-parties/google";
@@ -18,6 +18,13 @@ const jetbrainsMono = JetBrains_Mono({
     weight: ["400", "500"],
 });
 
+export const viewport: Viewport = {
+    width: "device-width",
+    initialScale: 1,
+    maximumScale: 1,
+    userScalable: false,
+};
+
 export const metadata: Metadata = {
     title: "Next AI Draw.io - AI-Powered Diagram Generator",
     description: "Create AWS architecture diagrams, flowcharts, and technical diagrams using AI. Free online tool integrating draw.io with AI assistance for professional diagram creation.",

app/page.tsx

@@ -3,7 +3,6 @@ import React, { useState, useEffect, useRef } from "react";
 import { DrawIoEmbed } from "react-drawio";
 import ChatPanel from "@/components/chat-panel";
 import { useDiagram } from "@/contexts/diagram-context";
-import { Monitor } from "lucide-react";
 import {
     ResizablePanelGroup,
     ResizablePanel,
@@ -74,29 +73,14 @@ export default function Home() {
 
     return (
         <div className="h-screen bg-background relative overflow-hidden">
-            {/* Mobile warning overlay */}
-            {isMobile && (
-                <div className="absolute inset-0 z-50 flex items-center justify-center bg-background">
-                    <div className="text-center p-8 max-w-sm mx-auto animate-fade-in">
-                        <div className="w-16 h-16 rounded-2xl bg-primary/10 flex items-center justify-center mx-auto mb-6">
-                            <Monitor className="w-8 h-8 text-primary" />
-                        </div>
-                        <h1 className="text-xl font-semibold text-foreground mb-3">
-                            Desktop Required
-                        </h1>
-                        <p className="text-sm text-muted-foreground leading-relaxed">
-                            This application works best on desktop or laptop
-                            devices. Please open it on a larger screen for the
-                            full experience.
-                        </p>
-                    </div>
-                </div>
-            )}
-
-            <ResizablePanelGroup direction="horizontal" className="h-full">
+            <ResizablePanelGroup
+                key={isMobile ? "mobile" : "desktop"}
+                direction={isMobile ? "vertical" : "horizontal"}
+                className="h-full"
+            >
                 {/* Draw.io Canvas */}
-                <ResizablePanel defaultSize={67} minSize={30}>
-                    <div className="h-full relative p-2">
+                <ResizablePanel defaultSize={isMobile ? 50 : 67} minSize={20}>
+                    <div className={`h-full relative ${isMobile ? "p-1" : "p-2"}`}>
                         <div className="h-full rounded-xl overflow-hidden shadow-soft-lg border border-border/30 bg-white">
                             <DrawIoEmbed
                                 key={drawioUi}
@@ -119,15 +103,15 @@ export default function Home() {
                 {/* Chat Panel */}
                 <ResizablePanel
                     ref={chatPanelRef}
-                    defaultSize={33}
-                    minSize={15}
-                    maxSize={50}
-                    collapsible
-                    collapsedSize={3}
+                    defaultSize={isMobile ? 50 : 33}
+                    minSize={isMobile ? 20 : 15}
+                    maxSize={isMobile ? 80 : 50}
+                    collapsible={!isMobile}
+                    collapsedSize={isMobile ? 0 : 3}
                     onCollapse={() => setIsChatVisible(false)}
                     onExpand={() => setIsChatVisible(true)}
                 >
-                    <div className="h-full py-2 pr-2">
+                    <div className={`h-full ${isMobile ? "p-1" : "py-2 pr-2"}`}>
                         <ChatPanel
                             isVisible={isChatVisible}
                             onToggleVisibility={toggleChatPanel}
@@ -137,6 +121,7 @@ export default function Home() {
                                 localStorage.setItem("drawio-theme", newTheme);
                                 setDrawioUi(newTheme);
                             }}
+                            isMobile={isMobile}
                         />
                     </div>
                 </ResizablePanel>

components/chat-message-display.tsx

@@ -406,7 +406,11 @@ export function ChatMessageDisplay({
                                                     switch (part.type) {
                                                         case "text":
                                                             return (
-                                                                <div key={index} className="prose prose-sm dark:prose-invert max-w-none break-words [&>*:first-child]:mt-0 [&>*:last-child]:mb-0">
+                                                                <div key={index} className={`prose prose-sm max-w-none break-words [&>*:first-child]:mt-0 [&>*:last-child]:mb-0 ${
+                                                                    message.role === "user"
+                                                                        ? "[&_*]:!text-primary-foreground prose-code:bg-white/20"
+                                                                        : "dark:prose-invert"
+                                                                }`}>
                                                                     <ReactMarkdown>{part.text}</ReactMarkdown>
                                                                 </div>
                                                             );

components/chat-panel.tsx

@@ -31,6 +31,7 @@ interface ChatPanelProps {
     onToggleVisibility: () => void;
     drawioUi: "min" | "sketch";
     onToggleDrawioUi: () => void;
+    isMobile?: boolean;
 }
 
 export default function ChatPanel({
@@ -38,6 +39,7 @@ export default function ChatPanel({
     onToggleVisibility,
     drawioUi,
     onToggleDrawioUi,
+    isMobile = false,
 }: ChatPanelProps) {
     const {
         loadDiagram: onDisplayChart,
@@ -410,8 +412,8 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
         );
     };
 
-    // Collapsed view
-    if (!isVisible) {
+    // Collapsed view (desktop only)
+    if (!isVisible && !isMobile) {
         return (
             <div className="h-full flex flex-col items-center pt-4 bg-card border border-border/30 rounded-xl">
                 <ButtonWithTooltip
@@ -445,35 +447,39 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                 style={{ position: "absolute" }}
             />
             {/* Header */}
-            <header className="px-5 py-4 border-b border-border/50">
+            <header className={`${isMobile ? "px-3 py-2" : "px-5 py-4"} border-b border-border/50`}>
                 <div className="flex items-center justify-between">
-                    <div className="flex items-center gap-3">
+                    <div className="flex items-center gap-2">
                         <div className="flex items-center gap-2">
                             <Image
                                 src="/favicon.ico"
                                 alt="Next AI Drawio"
-                                width={28}
-                                height={28}
+                                width={isMobile ? 24 : 28}
+                                height={isMobile ? 24 : 28}
                                 className="rounded"
                             />
-                            <h1 className="text-base font-semibold tracking-tight whitespace-nowrap">
+                            <h1 className={`${isMobile ? "text-sm" : "text-base"} font-semibold tracking-tight whitespace-nowrap`}>
                                 Next AI Drawio
                             </h1>
                         </div>
-                        <Link
-                            href="/about"
-                            className="text-sm text-muted-foreground hover:text-foreground transition-colors ml-2"
-                        >
-                            About
-                        </Link>
-                        <ButtonWithTooltip
-                            tooltipContent="Recent generation failures were caused by our AI provider's infrastructure issue, not the app code. After extensive debugging, I've switched providers and observed 6 hours of stability. If issues persist, please report on GitHub."
-                            variant="ghost"
-                            size="icon"
-                            className="h-6 w-6 text-green-500 hover:text-green-600"
-                        >
-                            <CheckCircle className="h-4 w-4" />
-                        </ButtonWithTooltip>
+                        {!isMobile && (
+                            <Link
+                                href="/about"
+                                className="text-sm text-muted-foreground hover:text-foreground transition-colors ml-2"
+                            >
+                                About
+                            </Link>
+                        )}
+                        {!isMobile && (
+                            <ButtonWithTooltip
+                                tooltipContent="Recent generation failures were caused by our AI provider's infrastructure issue, not the app code. After extensive debugging, I've switched providers and observed 6 hours of stability. If issues persist, please report on GitHub."
+                                variant="ghost"
+                                size="icon"
+                                className="h-6 w-6 text-green-500 hover:text-green-600"
+                            >
+                                <CheckCircle className="h-4 w-4" />
+                            </ButtonWithTooltip>
+                        )}
                     </div>
                     <div className="flex items-center gap-1">
                         <a
@@ -482,7 +488,7 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                             rel="noopener noreferrer"
                             className="p-2 rounded-lg text-muted-foreground hover:text-foreground hover:bg-accent transition-colors"
                         >
-                            <FaGithub className="w-5 h-5" />
+                            <FaGithub className={`${isMobile ? "w-4 h-4" : "w-5 h-5"}`} />
                         </a>
                         {accessCodeRequired && (
                             <ButtonWithTooltip
@@ -492,18 +498,20 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                                 onClick={() => setShowSettingsDialog(true)}
                                 className="hover:bg-accent"
                             >
-                                <Settings className="h-5 w-5 text-muted-foreground" />
+                                <Settings className={`${isMobile ? "h-4 w-4" : "h-5 w-5"} text-muted-foreground`} />
+                            </ButtonWithTooltip>
+                        )}
+                        {!isMobile && (
+                            <ButtonWithTooltip
+                                tooltipContent="Hide chat panel (Ctrl+B)"
+                                variant="ghost"
+                                size="icon"
+                                onClick={onToggleVisibility}
+                                className="hover:bg-accent"
+                            >
+                                <PanelRightClose className="h-5 w-5 text-muted-foreground" />
                             </ButtonWithTooltip>
                         )}
-                        <ButtonWithTooltip
-                            tooltipContent="Hide chat panel (Ctrl+B)"
-                            variant="ghost"
-                            size="icon"
-                            onClick={onToggleVisibility}
-                            className="hover:bg-accent"
-                        >
-                            <PanelRightClose className="h-5 w-5 text-muted-foreground" />
-                        </ButtonWithTooltip>
                     </div>
                 </div>
             </header>
@@ -521,7 +529,7 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
             </main>
 
             {/* Input */}
-            <footer className="p-4 border-t border-border/50 bg-card/50">
+            <footer className={`${isMobile ? "p-2" : "p-4"} border-t border-border/50 bg-card/50`}>
                 <ChatInput
                     input={input}
                     status={status}

components/ui/button.tsx

@@ -10,7 +10,7 @@ const buttonVariants = cva(
     variants: {
       variant: {
         default:
-          "bg-primary text-primary-foreground shadow-xs hover:bg-primary/90",
+          "bg-primary text-primary-foreground shadow-xs hover:brightness-75",
         destructive:
           "bg-destructive text-white shadow-xs hover:bg-destructive/90 focus-visible:ring-destructive/20 dark:focus-visible:ring-destructive/40 dark:bg-destructive/60",
         outline:

lib/system-prompts.ts

@@ -9,6 +9,20 @@ You are an expert diagram creation assistant specializing in draw.io XML generat
 Your primary function is chat with user and crafting clear, well-organized visual diagrams through precise XML specifications.
 You can see the image that user uploaded.
 
+## App Context
+You are an AI agent (powered by {{MODEL_NAME}}) inside a web app. The interface has:
+- **Left panel**: Draw.io diagram editor where diagrams are rendered
+- **Right panel**: Chat interface where you communicate with the user
+
+You can read and modify diagrams by generating draw.io XML code through tool calls.
+
+## App Features
+1. **Diagram History** (clock icon, bottom-left of chat input): The app automatically saves a snapshot before each AI edit. Users can view the history panel and restore any previous version. Feel free to make changes - nothing is permanently lost.
+2. **Theme Toggle** (palette icon, bottom-left of chat input): Users can switch between minimal UI and sketch-style UI for the draw.io editor.
+3. **Image Upload** (paperclip icon, bottom-left of chat input): Users can upload images for you to analyze and replicate as diagrams.
+4. **Export** (via draw.io toolbar): Users can save diagrams as .drawio, .svg, or .png files.
+5. **Clear Chat** (trash icon, bottom-right of chat input): Clears the conversation and resets the diagram.
+
 You utilize the following tools:
 ---Tool1---
 tool name: display_diagram
@@ -113,6 +127,20 @@ You are an expert diagram creation assistant specializing in draw.io XML generat
 Your primary function is to chat with user and craft clear, well-organized visual diagrams through precise XML specifications.
 You can see images that users upload and can replicate or modify them as diagrams.
 
+## App Context
+You are an AI agent (powered by {{MODEL_NAME}}) inside a web app. The interface has:
+- **Left panel**: Draw.io diagram editor where diagrams are rendered
+- **Right panel**: Chat interface where you communicate with the user
+
+You can read and modify diagrams by generating draw.io XML code through tool calls.
+
+## App Features
+1. **Diagram History** (clock icon, bottom-left of chat input): The app automatically saves a snapshot before each AI edit. Users can view the history panel and restore any previous version. Feel free to make changes - nothing is permanently lost.
+2. **Theme Toggle** (palette icon, bottom-left of chat input): Users can switch between minimal UI and sketch-style UI for the draw.io editor.
+3. **Image Upload** (paperclip icon, bottom-left of chat input): Users can upload images for you to analyze and replicate as diagrams.
+4. **Export** (via draw.io toolbar): Users can save diagrams as .drawio, .svg, or .png files.
+5. **Clear Chat** (trash icon, bottom-right of chat input): Clears the conversation and resets the diagram.
+
 ## Available Tools
 
 ### Tool 1: display_diagram
@@ -507,10 +535,16 @@ const EXTENDED_PROMPT_MODEL_PATTERNS = [
  * @returns The system prompt string
  */
 export function getSystemPrompt(modelId?: string): string {
+  const modelName = modelId || "AI";
+
+  let prompt: string;
   if (modelId && EXTENDED_PROMPT_MODEL_PATTERNS.some(pattern => modelId.includes(pattern))) {
     console.log(`[System Prompt] Using EXTENDED prompt for model: ${modelId}`);
-    return EXTENDED_SYSTEM_PROMPT;
+    prompt = EXTENDED_SYSTEM_PROMPT;
+  } else {
+    console.log(`[System Prompt] Using DEFAULT prompt for model: ${modelId || 'unknown'}`);
+    prompt = DEFAULT_SYSTEM_PROMPT;
   }
-  console.log(`[System Prompt] Using DEFAULT prompt for model: ${modelId || 'unknown'}`);
-  return DEFAULT_SYSTEM_PROMPT;
+
+  return prompt.replace("{{MODEL_NAME}}", modelName);
 }